Prior to entering an “immediately dangerous to life and health” (IDLH) environment, a firefighter will put on personal protective equipment which may include a fire-retardant hood, often used with a self-contained breathing apparatus (SCBA) mask. However, the firefighter still needs to maintain radio contact with other firefighters, a dispatch, and the like when the IDLH environment is entered.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the present invention.
The apparatus and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.